 (defn rand-physical-quantity []
   (rand-nth physical-quantities))
 
-(def quantity-unit-map {:density                [:lb-per-cu-ft :kg-per-m3]
+(def quantity-unit-map {:angle                  [:deg]
+                        :duration               [:min]
+                        :density                [:lb-per-cu-ft :kg-per-m3]
                         :energy                 [:ft-lb :J]
                         :force                  [:lbf :N]
                         :length                 [:ft :m]

       :hp (power-as (typical-power :W) :hp)))))

(def quantity-generate-measurement-map
  {:density                typical-density
   :energy                 typical-total-pump-energy
   :force                  typical-force
   :length                 typical-stage-length

  (tuc/draw-normal 92.2 2.4))

(defn typical-azimuth [plot-angle]
  (make-measurement (tuc/draw-normal plot-angle 1.24) :deg))

(defn make-line-generator [[m b]]
  (fn [t]
